It is one of the solar system's great mysteries, but proof of life on Mars could be just months away after a probe began searching for gasses linked to living organisms.
The 3.5-tonne spacecraft launched in March 2016 was part of a joint venture between the European Space Agency and the Russian-based Roscosmos.
The Trace Gas Orbiter (TGO), part of the ExoMars mission, then spent a year orbiting the Red Planet and last week sent out sensors to try and determine the origins of the methane gas in the atmosphere.
After completing more then 1,000 loops scientists hope it will be able to solve one of the great Martian mysteries - why methane, a possible signature of life, is being released on the planet.
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| Mars’ Olympus Mons – a shield volcano that scientists believe may still be active – is thrice the height of Mount Everest and the highest volcano in the Solar System. It stands at about 16 miles (25 km) high, has a diameter of 374 miles (624 km), and occupies about the same area as mainland France. |
Although it could take a year to compile all the data, scientists hope in the next few months they will get vital clues as to whether the gasses that have been detected on Earth's closest neighbour in recent years are geological in origin or were produced by living organisms.
Håkan Svedhem, the orbiter’s project scientist, said: “We will start our science mission in just a couple of weeks and are extremely excited about what the first measurements will reveal.
“We have the sensitivity to detect rare gases in minute proportions, with the potential to discover if Mars is still active today – biologically or geologically speaking.”
Although not one of the primary gases in Earth's atmosphere, methane is one of the most plentiful organic compounds on the planet and makes up the majority of natural gas.
It gets released whenever fossil fuels are extracted from the ground and is also produced through man-made methods such as livestock farming and landfill sites.
Pia Mitschdoerfer, Trace Gas Orbiter mission manager, said: “This is a major milestone for our ExoMars programme, and a fantastic achievement for Europe.
“We have reached this orbit for the first time through aerobraking and with the heaviest orbiter ever sent to the Red Planet, ready to start searching for signs of life from orbit.”
Astronomers have found traces of methane on the Red Planet on several previous missions, including in 2004, when Europe’s Mars Express orbiter detected levels of methane in the atmosphere, then ten years later, Nasa’s Curiosity rover recorded the presence of the gas on the surface.
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| Named after the Roman god of war, Mars is the fourth planet from the Sun and last of the terrestrial planets. It is called the Red Planet because of the brownish-red color of its surface. Chinese astronomers call Mars the “fire star” while ancient Egyptian priests called it “Her Desher,” meaning “the red one.” |
